To describe two-place physical problems, many possible models named Alice-Bob
(AB) systems are proposed. To find and to solve these systems, the Parity (P),
time reversal (T), charge conjugation (C), shifted-parity (Psβ, parity with a
shift), delayed time reversal (Tdβ, time reversal with a delay) and their
possible combinations such as PT, PC, PsβC, PsβTdβ and PsβTdβC etc. can
be successively used. Especially, some special types of Psβ-Tdβ-C group
invariant multi-soliton solutions for the KdV-KP-Toda type, mKdV-sG type, NLS
type and discrete H1β type AB systems are explicitly constructed.Comment: 22 page